Results 121 to 130 of about 35,734 (288)

A convenient and efficient synthesis of (S)-lysine and (S)-arginine homologues via olefin cross-metathesis

, 2005
A convenient five step synthesis of (S)-homolysine, incorporating a key olefin cross-metathesis step in the chain extension methodology, has been developed, together with a six step related synthesis of a new homologue of arginine, (S ...
Paul Keller (19587565), John Bremner (19588816), Timothy Boyle (20116608), Jonathan A Coates (20203086), Stephen Pyne (19586047)   +4 more
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Deacylative alkylation (DaA) of N-methyl-3-acetyl-2-oxindole for the synthesis of symmetrically 3,3-disubstituted 2-oxindoles. An access gate to anticancer agents and natural products.

Anais da Academia Brasileira de Ciências
The synthesis of 3,3-disubstituted N-methyloxindoles, starting from 3-acetyl-2-hydroxy-1-methyloxindole employing a sequential one-pot synthesis, is studied. The process involves a first alkylation in the presence of 1 equiv.
CRISTINA MORENO-CABRERIZO, AITOR ORTEGA-MARTÍNEZ, CYNTHIA MOLINA, CARMEN NÁJERA, JOSÉ M. SANSANO   +4 more
doaj   +1 more source

Ring-opening metathesis activity of ruthenium-based olefin metathesis catalyst coordinated with 1,3-bis(2,6-diisopropylphenyl)-4,5dihydroimidazoline

, 2007
A 1,3-bis-(2,6-diisopropylphenyl)-4,5-dihydroimidazol-2-ylidene substituted ruthenium (Ru)-based complex (4) has been prepared starting from (PCy3)(2)(Cl Ru=CHPh (2).
Verpoort, FrancisUGent8010008471899742796108960000-0002-5184-5500F49CC820-F0ED-11E1-A9DE-61C894A0A6B4, Imamoglu, Yeditor, Karabulut, Solmaz, Dragutan, Veditor   +3 more
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Z‑Trisubstituted α,β-Unsaturated Esters and Acid Fluorides through Stereocontrolled Catalytic Cross-Metathesis

Catalytic cross-metathesis (CM) reactions that can generate trisubstituted alkenes in high stereoisomeric purity are important but remain limited in scope.
Tobias Koengeter (14530140), Amir H. Hoveyda (1306548), Yucheng Mu (1429195), K. N. Houk (1247004), Fengyue Zhao (4902886), Can Qin (6388685), Fang Liu (13271)   +6 more
core   +1 more source

Synthesis of Medium-Sized Carbocycles by Gallium-Catalyzed Tandem Carbonyl-Olefin Metathesis/Transfer Hydrogenation

, 2019
We report a catalytic tandem process involving a ring-closing carbonyl-olefin metathesis and a transfer hydrogenation. 1,4-Cyclohexadiene has been used as H2 surrogate to reduce the cyclic alkenes formed after the metathesis step. The same NHC-stabilized
Vincent, Gandon, Régis, Guillot, Marie, Vayer, Jean Pierre, Baltaze, Christophe, Bour, Zhilong, Li, Alexandre, Djurovic   +6 more
core   +1 more source

Iconicity as the motivation for morphophonological metathesis and truncation in Nigerian Pidgin

Open Linguistics
We present evidence for iconicity as the motivation for two patterns of morphophonological alternation in Nigerian Pidgin, also known as Naijá. To express an ‘unconventional positive’ in all varieties of Naijá, some nouns with the tone melodies H-L and L-
Akinbo Samuel Kayode, Ekiugbo Philip Oghenesuowho   +1 more
doaj   +1 more source

The synthesis and characterization of conjugated polyradicals: an approach to organic magnets [PDF]

, 1990
The thesis describes investigations into the preparation and magnetic properties of new conjugated polymers, with pendant free radical sites, produced from substituted acetylenes.
Alexander, Cameron
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The activation mechanism of Fe-based olefin metathesis catalysts

, 2014
Density functional theory calculations have been used to describe the first turnover for olefin metathesis reaction of a homogenous Fe-based catalyst bearing a N-heterocyclic carbene ligand with methoxyethene as a substrate.
Vummaleti, Sai Vikrama Chaitanya, Cavallo, Luigi, Vummaleti, Sai V. C., Poater Teixidor, Albert, Pump, Eva, Poater, Albert   +5 more
core   +1 more source

Comparing Ru and Fe-catalyzed olefin metathesis

, 2014
Density functional theory calculations have been used to explore the potential of Fe-based complexes with an N-heterocyclic carbene ligand, as olefin metathesis catalysts.
Vummaleti, Sai Vikrama Chaitanya, Cavallo, Luigi, Vummaleti, Sai V. C., Poater Teixidor, Albert, Pump, Eva, Poater, Albert   +5 more
core   +1 more source

2.10 Ring-Closing Metathesis

, 2016
Ring-closing metathesis (RCM) has emerged as a powerful synthetic tool. Depending on the unsaturated functional groups involved, ring-closing-metathesis reactions are classified into three categories: diene ring-closing metathesis, enyne ring-closing ...
D. Lee, V. R. Sabbasani
core   +1 more source